Articles

A Primary Study on the Environment of Frozen Ground in the Nam Co Basin, Tibet

Expand
  • 1. Nam Co Station of Multi-sphere Interaction Observation and Research, Institute of Tibetan Plateau Research, CAS, Beijing 100085, China; 2. Key Laboratory of Ice Core and Cold Region Environment, CAREERI, CAS, Lanzhou  730000, China

Received date: 2006-10-11

  Revised date: 2006-11-03

  Online published: 2006-12-15

Abstract

Based on the data from two automatic weather stations (AWS) with 4-layers of soil probes located at an elevation of 5,400m at the Northern slope of Mt. Nyenquentanglha (N) and at 4,720 m at Boji (B) in the northwest of the Nam Co lake, this paper analyzed the environment of the frozen ground around the lake basin. It concludes that from September 2005 to May 2006, the daily temperature and monthly temperature at the N were both lower than those at the B, however, amplitude of daily temperature at the N was smaller than that at the BJ. The freezing period of ground at the N is longer than that at the B. From September to next May, their air temperature lapse rate is 0.31℃/100 m smaller than that in the atmosphere. Results show alpine permafrost existed at the N by comparing monthly temperature with the Ando, Tibet. Heat conduction between air and soil and within soil at the N was faster than that at the B. During freezing period, a powerful relationship was found between the soil unfrozen water content and soil temperature, the unfrozen water content abruptly declined at 0~-2℃. The Diurnal variation of soil temperature is dramatic at the 0~40 cm depth, while no trend below 40 cm; so does soil unfrozen water content at 5 cm depth, no trend below 20 cm. Based on the close correlation between a soil freezing depth (Df) and a cumulative frost temperature (Tg), the model was proposed as the following: Df-n= 0.0016Tg+ 1.69 at the N and Df-b= 0.002Tg+ 1.13 at the B, using the model, the maximum freezing depth were estimated by 1.69 m and 1.13 m at the two sites, respectively.

Cite this article

Tian Keming,Liu Jingshi,Kang Shichang,Li Chaoliu . A Primary Study on the Environment of Frozen Ground in the Nam Co Basin, Tibet[J]. Advances in Earth Science, 2006 , 21(12) : 1324 -1332 . DOI: 10.11867/j.issn.1001-8166.2006.12.1324

References

[1] Zhou Youwu, Guo Dongxin, Cheng Guodong, et al. Geocryology in China[M]. Beijing:Science Press,2000.299-360. [周幼吾,郭东信,程国栋,.中国冻土[M].北京:科学出版社,2000:299-360.]

[2] Zhao Lin, Cheng Guodong, Li Shuxun, et al. The freezing and thawing process of permafrost active layer in the region near Wudaoliang of Tibetan Plateau[J]. Science Bulletin,2000,45 (11):1 205-1 211.[赵林,程国栋,李述训,.青藏高原五道梁附近多年冻土活动层冻结和融化过程[J].科学通报,2000,45 (11):1 205-1 211.]

[3] Wang Chenghai, Dong Wenjie, Wei Zhigang. The feature of seasonal frozen soil on Qinghai-Tibet Plateau[J]. Acta Geographica Sinica,2001,56(5):523-531.[王澄海,董文杰,韦志刚.青藏高原季节性冻土年际变化的异常特征[J].地理学报,2001,56(5):523-531.

[4] Gao Rong, Wei Zhigang, Dong Wenjie. Inter-annual change of the beginning and ending freezing date of soil in Tibetan Plateau[J]. Journal of Glaciology and Geocryology,2003,25(1):49-54.[高荣,韦志刚,董文杰.青藏高原土壤冻结始日和终日的年际变化[J].冰川冻土,2003,25(1):49-54.]

[5] Li Shuxun, Cheng Guodong, Guo Dongxin. The future thermal regime of numerical simulate in permafrost on Qinghai-Tibet Plateau,China,under climate warming[J]. Science in China(Series D),1996,39(4):434-441.[李述训,程国栋,郭东信. 气候转暖条件下青藏高原多年冻土变化趋势[J].中国科学:D,1996,39(4):434-441.]

[6] Wang Shaoling. Discussion on frozen ground degradation and frozen ground environment in Tibetan Plateau[C]Fifth National Assembly Papers on Glaciers and Permafrost (on the list). Lanzhou:Gansu Culture Press,1996:11-17.[王绍令,冻土退化与青藏高原冻土环境问题探讨.[C]第五届全国冰川冻土学大会论文集(上册).兰州:甘肃文化出版社,1996:11-17.]

[7] Ding Yongjian, Ye Baisheng, Liu Shiyin, et al. Geocryological and hydrological monitoring and research at large scale in Tibetan Plateau[J]. Science Bulletin,2000,45(2):208-214.[丁永建,叶佰生,刘时银,.青藏高原大尺度冻土水文监测研究[J].科学通报,2000,45(2):208-214.]

[8] Li Shuxun, Cheng Guodong. Water and Thermal Transformation in Freezing-thawing Soil[M]. Lanzhou: Lanzhou University Press, 1993:36-202.[李述训,程国栋. 冻融土中的水热输运问题[M].兰州:兰州大学出版社,1993:36-202.]

[9] Wang Shaoling, Zhao Xinmin. Analysis of the ground temperature monitored in permafrost region on Tibet plateau[J]. Journal of Glaciology and Geocryology,1999,21(2):159-163.[王绍令,赵新民.青藏高原多年冻土区地温监测结果分析[J].冰川冻土,1999,21(2):159-163.]

[10] Li Shude, Cheng Guodong. Distribution Map of Frozen Ground in Tibetan Plateau[M]. Lanzhou: Gansu Culture Press,1996. [李树德,程国栋.青藏高原冻土分布图[M].兰州:甘肃文化出版社,1996.]

[11] Nan Zhuotong, Li Shuxun, Liu Yongzhi. Mean annual ground temperature distribution on the Tibetan Plateau:Permafrost distribution mapping and further application[J]. Journal of Glaciology and Geocryology, 2002, 24(2):142-148. [南卓铜,李述训,刘永智.基于年平均地温的青藏高原冻土分布制图及应用[J].冰川冻土,2002,24(2):142-148.]

[12] Li S X, Chen R J. Simulation of the thermal regime of permafrost in northeast China under climate warming[C]Proceedings on the 7th International Permafrost Conference. Universite Laval,1998:651-656.

[13] Li X,Cheng G D,Chen X Z. Response of permafrost to global change on the Qinghai-Xizang plateau a GIS aided model[C]Proceedings on the 7th International Permafrost Conference.Universite Laval,1998:657-622.

[14] Wu Zhonghai. The geological record of climate and environment change in Holocene Epoch in Nam co and neighbor region of Tibet[J]. Journal of Glaciology and Geocryology,2004,26(3) :275-283. [吴中海.西藏纳木错及邻区全新世气候与环境变化的地质记录[J].冰川冻土,2004,26(3) :275-283.]

[15] Jingshi Liu, Hayakawa N, Lu M J, et al. Hydrological and geocryological response of winter streamflow to climate warming in Northeast China[J]. Cold Regions Science and Technology,2003,37:15-24.

[16] Lovell C W. Temperature effects on phase composition and strength of partially-frozen soil[J]. Highway Research Board Bulletin,1957,168:74-95.

Outlines

/